Chronic phase chronic myeloid leukemia: response of imatinib mesylate and significance of Sokal score, age and disease duration in predicting the hematological and cytogenetic response.

Objective: To evaluate the response of imatinib mesylate in chronic phase of chronic myeloid leukemia and to observe the significance of Sokal score and various factors which predict the response.
Methods: This was a descriptive, prospective study conducted from May 2001 to September 2006. One hundred and thirty six patients with diagnosis of chronic myeloid leukemia in chronic phase were analyzed. Hematologic and cytogenetic responses were assessed according to defined criteria.
Results: The median age at time of diagnosis was 33 years (range, 12-65 years). Among them 86 were males, 50 were females. At the end of study response was analyzed overall and according to Sokal score. At median follow-up of 18 months, 122 patients were evaluable for cytogenetic response. Complete hematologic response was seen 86% while complete and major cytogenetic response was observed in 34.4% and 49.2% cases respectively. Analysis of variables like younger age, disease duration at time of starting imatinib failed to show any significant influence on response to imatinib mesylate, however, response was found to be higher in patients who had low Sokal score at the time of presentation.
Conclusion: Imatinib mesylate has substantial activity in chronic phase of CML. Low Sokal score at time of presentation predict the higher hematologic as well as cytogenetic response in patients with chronic phase.